During arthroplasty procedures, the implant region is generally prepared by shaving or resecting segments of the bone. In knee replacement surgery, a proximal portion of the tibia and a distal portion of the femur are generally resected to be sized to receive the implant. Cuts are made using various saws, drills or other grinding or shaving tools.
To assist in resection, surgical guides may be used with the saw to ensure that the cut angles and dimensions conform to the implant. Various techniques require the sequential use of a single surgical guide, such as a cutting block, or several surgical guides to make a plurality of cuts in a plurality of dimensions and angles. For example, a cutting block or guide may be used to engage the distal portion of the femur to resect the bone to receive the femoral portion of the knee implant. Subsequently, the same or a different cutting block may be used to engage the proximal portion of the tibia to resect the bone to receive the tibial portion of the knee implant. Therefore, it may be beneficial to have an easily repositionable cutting block.
Along with having an easily repositionable cutting block, it is sometimes desirable to have the cutting block remain stationary during portions of or throughout the selected resection even while the saw or drill is vibrating or oscillating. An unplanned movement of the cutting block may result in saw shifting and an improper bone resection being made, which may impact the fit and function of the implant.
As a further surgical supplement to the cutting guides, fixation pins may be used. The fixation pin may be interconnected with the cutting guide and the bone through a drilled hole or tunnel in the bone to make the cutting block generally immobile while the saw is vibrating. After the desired cut has been made, the fixation pin and the cutting guide are removed. Depending on the type of cutting guide used and the extent or quantity of resections made during the procedure, the cutting guide and fixation pin may be used in several locations during the procedure.
It may be desirable to have a fixation pin that provides enhanced fit in the bone and enhanced security of the cutting guide to a bone region while performing a selected procedure.